Autopsy case of linear nevus sebaceous syndrome with KRAS (G12D) mutation.

Linear nevus sebaceous syndrome (LNSS) is a neurocutaneous syndrome associated with systemic complications that involve multiple organs, including the skin, central nervous system, eyes, and skeleton. LNSS is considered to be caused by mosaic RAS gene mutation. In this report, we present an autopsy case of LNSS in a Japanese boy. The affected neonate had hydrops fetalis and was born at 28 weeks and 4 days of gestation, weighing 2104 g. He had bilateral inverted eyelids, verrucous linear nevus separated along Blaschko's line, myocardial hypertrophy, and pharyngeal constriction, and underwent intensive treatment in NICU for arrhythmia, hydrocephalus, and respiratory distress. The hydrocephalus progressed gradually and he died at the age of 181 days, 12 days after a sudden cardiac arrest and recovery. KRAS G12D mutation was found in a skin biopsy specimen but not in blood cells, suggesting a postzygotic mosaicism. Autopsy revealed novel pathological findings related to LNSS, including intracranial lipomatous hamartoma and mesenteric lymphangioma, in addition to previously reported findings such as multicystic dysplastic kidney. There was the limited expression of mutated KRAS protein in kidneys.

Next generation sequencing aids diagnosis and management in a case of encephalocraniocutaneous lipomatosis.

Encephalocraniocutaneous lipomatosis (ECCL) is a rare neurocutaneous disorder caused by somatic FGFR1 and KRAS variants. It shares significant phenotypic overlap with several closely related disorders caused by mutations in the RAS-MAPK pathway (mosaic RASopathies). We report a diagnostically challenging case of ECCL in which next-generation sequencing of affected tissue identified a pathologic FGFR1 p.K656E variant, thereby establishing a molecular diagnosis. Patients with FGFR1-associated ECCL carry a risk of developing malignant brain tumors; thus, genetic testing of patients with suspected ECCL has important management implications.

Oral sialadenoma papilliferum with kras mutation in a patient with linear nevus sebaceous syndrome.

Linear nevus sebaceous syndrome (LNSS) is a rare neurocutaneous syndrome part of the epidermal nevus syndromes group, characterized by the presence of sebaceous nevi and other extracutaneous lesions genetically related to RAS family gene mutations. Sialadenoma papilliferum (SP) is a rare benign intraoral neoplasm which is usually BRAF or HRAS mutated. We report a case of a young female girl diagnosed with a LNSS who developed a SP which had a KRAS mutation. This is the first case of SP with a KRAS mutation in the context of a LNSS.

[Ocular manifestations and surgical treatment of the linear nevus sebaceous syndrome].

Objective: To report the clinical and pathological features and surgical treatment of the linear nevus sebaceous syndrome. Methods: It was a retrospective case series study. The clinical records of 11 patients (14 eyes) who were diagnosed as linear nevus sebaceous syndrome between April 2009 and February 2018 at Beijing Tongren Hospital were analyzed. Data collected included sex, age, clinical manifestations, disease site, pathological features, surgical treatment and therapeutic effects. Results: There were six males and five females, aged 6 months to 7 years (mean, 2.8 years). The nevus sebaceous was located at the head (9 patients), face (5 patients) and neck (3 patients). The most common ocular manifestations were blepharocoloboma (13 eyes) and external ocular mass (9 eyes). Surgical treatment was performed in 9 patients (11 eyes), including lid reconstruction in all these eyes, corneal and conjunctival mass resection in four patients (4 eyes), eyelid tumor resection in 5 patients (5 eyes), and symblepharon separation and conjunctival sac reconstruction in 3 patients (5 eyes). Pathological examinations of the external ocular, corneal and conjunctival masses (6 eyes) confirmed the diagnosis of complex choristoma. All operated patients had improved appearance. Conclusions: Linear nevus sebaceous syndrome has characteristic cutaneous lesions and ocular manifestations. Histopathologically, all epibulbar lesions prove to be complex choristomas. The appearance of patients with linear nevus sebaceous syndrome can be significantly improved by oculoplastic surgery. (Chin J Ophthalmol, 2020, 56: 846-852).

Linear Nevus Sebaceous Syndrome: Clinical Presentation and Management Considerations.

A relatively rare neurocutaneous condition known as linear nevus sebaceous syndrome (LNSS) is marked by a variety of symptoms as well as the unusual characteristics of developing mosaic RASopathies of phacomatoses. Mental retardation, seizures, and midline facial linear nevus sebaceous were the usual diagnostic triad. A hallmark of LNSS is the papillomatous growth of the epidermis, also known as nevus sebaceous. In this case report, we presented a case of a 13-year-old male with LNSS with a vascular conjunctival lesion and a coloboma of the optic disc.

Schimmelpenning-Feuerstein-Mims syndrome with orbital choristoma and KRAS mutation: a current review and novel case report.

INTRODUCTION: Schimmelpenning-Feurstein-Mims Syndrome (SFMS) is a rare neurocutaneous disorder. Herein, we describe a novel case and review the phenotypic spectrum and molecular findings of SFMS from an ophthalmology perspective. METHODS: Clinical case including presentation, management, pathology, and genetic analysis is described. A literature search on Schimmelpenning-Feuerstein-Mims and its synonyms, Linear nevus sebaceous syndrome, Organoid nevus syndrome, Jadassohn nevus phacomatosis, and Solomon syndrome, was conducted. An updated review and description of published cases with identified genetic mutations are described. RESULTS: A 13-year-old boy with SFMS presented with acute right eye pain and an enlarging orbital mass. Excisional biopsy of the mass revealed an orbital choristoma. Genetic analysis of the orbital tumor confirmed a KRAS c.35 G>A, p.G12D mutation. A literature search revealed 19 cases of SFMS with mutations in the RAS-pathway. KRAS, HRAS, and NRAS mutations were identified in 74%, 21%, and 5% of patients, respectively. Ophthalmic pathology was seen in 83% of patients. Systemic findings varied and involved the skin, central nervous system, and eyes most commonly. DISCUSSION: SFMS, a rare neurocutaneous disorder, results from postzygotic mosaic mutations in the RAS/MAPK pathway. Patients present with various systemic findings and ophthalmic manifestations occur in most cases. This is the first case description of a KRAS mutation identified in an orbital choristoma in SFMS. The disease is described under various names in the literature, and we propose that all syndromic cases with mosaic RAS mutations be reported under the eponym, SFMS.

Reversibility and developmental neuropathology of linear nevus sebaceous syndrome caused by dysregulation of the RAS pathway.

Linear nevus sebaceous syndrome (LNSS) is a neurocutaneous disorder caused by somatic gain-of-function mutations in KRAS or HRAS. LNSS brains have neurodevelopmental defects, including cerebral defects and epilepsy; however, its pathological mechanism and potentials for treatment are largely unclear. We show that introduction of KRASG12V in the developing mouse cortex results in subcortical nodular heterotopia and enhanced excitability, recapitulating major pathological manifestations of LNSS. Moreover, we show that decreased firing frequency of inhibitory neurons without KRASG12V expression leads to disrupted excitation and inhibition balance. Transcriptional profiling after destabilization domain-mediated clearance of KRASG12V in human neural progenitors and differentiating neurons identifies reversible functional networks underlying LNSS. Neurons expressing KRASG12V show molecular changes associated with delayed neuronal maturation, most of which are restored by KRASG12V clearance. These findings provide insights into the molecular networks underlying the reversibility of some of the neuropathologies observed in LNSS caused by dysregulation of the RAS pathway.

Renal Involvement in Linear Nevus Sebaceous Syndrome-An Underrecognized Feature.

Linear nevus sebaceous syndrome (LNSS) is a rare neurocutaneous disorder. It is characterized by the presence of nevus sebaceous, ocular anomalies, neurological deficits, and convulsion. Renal involvement was not commonly reported. We report a 10-year-old girl with LNSS who had concomitant cystic kidney disease and diffuse aortopathy with bilateral renal artery stenosis, leading to hypertension requiring oral anti-hypertensive medications. The girl presented with chorioretinal coloboma and multiple nevus sebaceous at birth. She had aortic coarctation and received surgical repair at one week of life. She had persistent hypertension during her follow-up. Further investigations were performed to look for causes of hypertension apart from possible re-coarctation. Her magnetic resonance angiogram revealed diffuse aortopathy, which extended from the aortic arch to the abdominal aorta. Branches of the aorta, including the celiac trunk, superior mesenteric arteries, and renal arteries, were also narrowed. Multiple renal cysts were also identified in her right kidney. Interventional angioplasty over the renal arteries was not feasible due to diffuse narrowing of the aorta, especially at the origins of renal arteries. The blood pressure was controlled with oral anti-hypertensive medications. Our case illustrated that pediatricians should be aware of the possible renal involvements in LNSS, which impose a significant impact on the management and long-term prognosis of these patients.

Ophthalmic Manifestation and Pathological Features in a Cohort of Patients With Linear Nevus Sebaceous Syndrome and Encephalocraniocutaneous Lipomatosis.

Purpose: This study aimed to figure out the association between ophthalmic and pathological features in patients with Linear Nevus Sebaceous Syndrome (LNSS) and in patients with Oculoectodermal Syndrome-Encephalocraniocutaneous Lipomatosis (OES-ECCL). Methods: It is a retrospective, non-consecutive, observational case series. Twenty-seven patients (12 with LNSS and 15 with OES-ECCL, 41 eyes) referred to the Department of Ophthalmology of the Shanghai Ninth People's Hospital between 2000 and 2020 were included. The mean age of the study population for the first-time consult was 5.7 years, ranging from 3 months to 34 years. Clinical notes, pathological records, and imaging findings were reviewed in all the patients. Results: Fourteen (51.9%) cases showed bilateral ocular involvement. Epibulbar choristomas were seen in all the patients. All the lesions involved the conjunctiva and cornea simultaneously. Multiple lesions were observed in 12 eyes. Of the 14 excised lesions, 11 were found to be complex choristomas. Further, 24 (89%) patients had eyelid coloboma. Also, 13 patients (48%) were diagnosed with strabismus, and 12 patients (44%) had abnormal fundus imaging, including optic nerve hypoplasia. Conclusions: LNSS and OES-ECCL shared common ophthalmic features, including epibulbar choristomas with distinctive characteristics, eyelid coloboma, strabismus, and optic nerve hypoplasia. The complex choristoma was found to be associated with the diseases. These specific patterns can be diagnostic clues to distinguish them from other syndromes, such as craniofacial defects, and to remind ophthalmologists that such patients require additional dermatological and neurological examinations and referral. Moreover, a thorough evaluation of ocular conditions is imperative for early interventions.

Linear Nevus Sebaceous Syndrome in a Child With Infantile Spasms and Focal Cortical Dysplasia.

Linear nevus sebaceous syndrome (LNSS) is a rare neurocutaneous syndrome with important neurological involvement including brain malformation, focal seizures, and developmental delay. We discuss a case with a unique presentation with localization-related infantile spasms and review the clinical and radiological features of this case. To our knowledge, there are no previously reported cases of LNSS with infantile spasms and cortical dysplasia. Therefore, the presented case will make an important contribution to the available knowledge.

Identification of KRAS mutation in a patient with linear nevus sebaceous syndrome: a case report.

BACKGROUND: Linear nevus sebaceous syndrome (LNSS) is a rare genetic disease characterized by large linear sebaceous nevus typically on the face, scalp, or neck. LNSS could be accompanied by multisystem disorders including the central nervous system. Herein, we report gene mutational profile via whole exome sequencing of both lesional and non-lesional skin samples in a LNSS patient. CASE PRESENTATION: A 17-year-old girl presented with multisystem abnormalities, including large skin lesions, ocular disorders, abnormal bone development and neurological symptoms. A diagnosis of LNSS was established based on clinical manifestations, histopathological and imaging findings. The skin lesions were resected and no recurrence was noted at the time of drafting this report. Whole exome sequencing of genomic DNA revealed the following 3 mutations in the lesions of the index patient: KRAS (c.35G > A, p.G12D), PRKRIR (c.A1674T, p.R558S), and RRP7A (c. C670T, p.R224W), but no mutation was found in the healthy skin and peripheral blood sample of the index patient, or in the blood samples of her parents and sibling. PCR-mediated Sanger sequencing of DNA derived from lesional skin sample of the index patient verified KRAS mutation, but not PRKRIR (c.A1674T, p.R558S) and RRP7A (c. C670T, p.R224W). None of the 3 mutations was found in Sanger sequencing in skin lesions of 60 other cases of nevus sebaceous patients. CONCLUSIONS: Our findings show the relevance of KRAS mutation to LNSS, providing new clues in understanding related genetic heterogeneity which could aid genetic counselling for LNSS patients.

Linear nevus sebaceous syndrome presenting as circumscribed choroidal hemangioma.

A 4-year-old female with a unilateral circumscribed choroidal hemangioma and secondary total exudative retinal detachment. A nasal skin scar-like lesion incised to confirm a histopathologic diagnosis of linear nevus sebaceous. Further imaging disclosed asymmetry of the lateral ventricle frontal horns, suggestive of the diagnosis of linear nevus sebaceous syndrome. The choroidal hemangioma was treated with I-125 episcleral brachytherapy (apical dose of 45 Gy). At 6 months post-radiation, the tumor showed regression with total resolution of exudative retinal detachment.

Linear nevus sebaceous syndrome in a neonate conceived by intracytoplasmic sperm injection.

Linear nevus sebaceous syndrome is a multisystem disorder including nevus sebaceous, which is the hallmark of this syndrome, together with central nervous system, ocular and skeletal anomalies. We report a case of extensive skin lesions, CNS and eye anomalies in a full term infant who was conceived by intracytoplasmic sperm injection.

Schimmelpenning syndrome with Didymosisaplasticosebacea in an infant

Introduction@#Schimmelpenning syndrome may encompass abnormalities of the cardiovascular, skeletal, ophthalmologic and urogenital systems. Nevus sebaceous is a hallmark finding and ophthalmologic findings are seen in 59% of the cases which include colobomas and choristomas.@*Case Summary@#A 1-month-old female presented with a verrucous plaque over the scalp and right zygomatic area upon birth. Physical examination reveals a linear yellowish alopecic verrucous plaque over the right frontal region, yellowish alopecic verrucous plaque topped with a skin colored papule over the right zygomatic region, conjunctival mass over the right eye and an atrophic patch with areas of circular erosion over the right occipital region. Ballard score and reflexes were appropriate for gestational age. Newborn screening was normal and otoacoustic-emission-test revealed no hearing loss. She was referred to an ophthalmologist and was assessed to have a lipodermoid, right upper eyelid and optic nerve coloboma. Cranial CT scan is unremarkable. Histopathology showed an increase in number of sebaceous glands with malformed hair units. She was managed holistically and does not have seizures and no secondary development of tumors in the nevus sebaceous.@*Conclusion@#Schimmelpenning syndrome is usually associated with the clinical triad of nevus sebaceous, mental retardation and seizures. In this case, seizures were absent, however, there is an associated lipodermoid, right upper eyelid and right optic nerve coloboma. In addition, she also presented with aplasia cutis congenita. Hence, it is important to look for other manifestations when patients present with nevus sebaceous because management requires collaboration with different specialties.

A Case of Linear Nevus Sebaceous Syndrome with Leptomeningeal Angioma and Skeletal Dysplasia / 대한소아신경학회지

Linear nevus sebaceous syndrome is a rare neurocutaneous syndrome characterized by linear sebaceous nevus, mental retardation, and seizures. We experienced a 20-months-old girl who showed manifestation of leptomeningeal angioma, lipodermoid on left eye, kyphoscoliosis, and developmental dysplasisa of the hip. We report this case with a review of related literature.